In which month does the rainy day fall?

Meiyu days are from June to July.

Meiyu refers to the continuous cloudy and rainy weather that occurs from early June to mid-July every year in the Gregorian calendar. At this time, due to the long period of sometimes rainy and sometimes sunny and high humidity weather, household utensils are prone to mold. , also known as mildew rain among the people. The Meiyu weather phenomenon mainly occurs in my country's Jiangnan District, the middle and lower reaches of the Yangtze River, Jianghuai District, and to South Korea and Japan.

The plum rain season is called plum rain because it is the ripening period of plums in the south of the Yangtze River. Influenced by Chinese traditional culture, South Korea calls it "Changma", which is vividly characterized as "long hair". It is called "Biau" in Japan, which is in the same vein as "mildew".

Meiyu is a unique product of the northward advance of the East Asian summer monsoon. It is a unique weather and climate phenomenon in East Asia. The plum rainy season is also the season with the most significant monsoon precipitation in my country. The climate characteristics of the plum rainy season are concentrated precipitation, heavy rainfall, few sunshine hours, cloudy weather, and weak wind.

Formation conditions

1. In the high latitudes of Asia, there is blocking high pressure or a stable high pressure ridge in the middle of the troposphere, and the atmospheric circulation is relatively stable and less changeable.

2. The westerly circulation in mid-latitudes is flat, and frequent shortwave activities provide cold air conditions for the Jianghuai region.

3. The western Pacific subtropical high has an obvious westward and northward jump process. The 500hPa subtropical high ridge is stable between 20 degrees and 25 degrees north latitude, and warm and moist air flows from the edge of the subtropical high to the Yangtze-Huaihe River Basin. Under such circulation conditions, the Meiyu front lingers in the Jianghuai basin, often accompanied by southwest vortices and shear lines, and mesoscale systems are active above the Meiyu front. It not only maintains continuous rainfall during the Meiyu period, but also provides abundant water vapor for heavy rains.

Reference for the above content: Baidu Encyclopedia—Meiyu